This combo is in a 2700# 4 speed manual trans car witha 3.70 gear in the transaxle.
355 SBC
197cc Canfield Aluminum Heads 72cc combustion 205/160 valve
Victor Jr Intake
Carb is a Quick Fuel Q Series DP 750
The Cam Comp cams solid roller .630 lift and duration at .050 is 252/258 106 lobe sep
all comp valve train and roller tip magnum rockers
Static Comp is 10.7:1
Distributor is mechanical Adv pro billet
6A Box
Combo is brand new and has a crisp throttle response and clean idle but it is really a slush box when driving from launch till end it just really is not responsive
My initial timing is 17-18* and have lightest springs and I believe black bushing anyways its the earliest full adv
I want to have car put on chassis dyno with wide band to tune the car but anything that sticks out and says no go on my combo or any suggestions??
If I can give any info more please ask I am just reaching out for help thanks guys at always
thanks for the replies everyone, I though I picked the right cam by matching rpm range to the intake but I dont know it said at comp that it makes power from 3500-6500 the pistons are trw forged .200 dome I looked it up and with 72cc heads it make around 10.7 comp any more help is great I mean should it be a big power maker at 3500 or 4k till 6500? I mean it is in a 2700# 4 speed car and the gears are kind of out of my hands since it is in the transaxle final drive
I think the power should come on as the cam manufacturer says it will. The intake and cam matching simply facilitates the cam doing its job. I think XNTRIK is correct also. For the gears you have, you need a milder cam to get good low end performance. And I agree further with him that 20-30 degrees lost from the duration would be a big help. I'm not too sure exactly how much I'd recommend losing, though. Losing 30 degrees would get the motor where I'd think it should be, but I think the dynamic compression might get problematic. Losing only 20 degrees would be better regarding dynamic compression, but I'm not sure it's enough cam change for the motor. If my memory is right (not too often) you are in CA, and are limited to 91 octane (like me!). I think I'd change the cam, losing 20 degrees, and plan on maybe also going to a dual plane intake to help bolster the low end.
I think I recall the discussions as this was going together. You were concerned the transaxle might not take a "boatload" of torque.
I dunno the whole solid lifter thing well but if it were mine(as far as Hydrualic specs go)I'd bring the cam down to about 234@.050 intake duration and I'd bring the LSA to 110 for a street car and I'd loss the Victor for a Torker(so what I like them) or Performer RPM.
First I have to conclude that your cam is degreed correctly.
I am curious as to the cranking compression (all plugs out, open throttle, and 8 strokes). 91 octane should stand 190 psi with a good tune. I bet that cam has it about 150.
Most rodders build at least one engine that is waaaay over cammed. It's a learning experience.
I will also note that sometimes a boarderline lean condition will have crisp throttle response under no load and but be too lean to pull decent power when accelerating the vehicle.
hey thanks guys plugs are hard to check on this motor after a run so I want to tune it with a wide band so I will have to just get it to the dyno and get everything sorted out I geuss I did over cam it however I geuss it will do for a while. It should still have plenty of power Id hope and maybe after a good tune the car should still make it into the 11's
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